Antenna and wireless ic device

ABSTRACT

An antenna for a wireless IC device having improved energy transfer efficiency with a wireless IC, and a wireless IC device equipped with the antenna are constructed such that the antenna includes a coil pattern and spiral coupling patterns provided at the ends of the coil pattern and disposed so as to face each other. A coupling module including a wireless IC chip and a feeder circuit substrate including a feeder circuit arranged to be coupled to the wireless IC chip is mounted on the coupling pattern so as to define a wireless IC device. The coil pattern is an open type coil pattern. The coupling patterns are arranged close to each other to define a single LC resonator. Thus, energy is concentrated in the coupling patterns, thereby improving the energy transfer efficiency between the antenna and the wireless IC chip.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an antenna and a wireless IC device,and more particularly, to an antenna for a wireless IC device used in anRFID (Radio Frequency Identification) system and a wireless IC deviceincluding the antenna.

2. Description of the Related Art

In general, RFID systems in which a reader/writer that generates anelectromagnetic wave and a wireless IC (referred to as an IC tag, awireless IC device, etc.) that is attached on an article, a container orother suitable object and stores predetermined information communicatewith each other in a non-contact manner to transfer information havebeen developed as a management system for articles. Communication withthe reader/writer is achieved by coupling the wireless IC with anantenna (emission plate).

As a wireless IC of this type, Japanese Unexamined Patent ApplicationPublication No. 10-293828 describes a wireless IC in which a coil L11 ofan ID module 100 and a coil L12 of an a coil module 110 are coupled andset to resonate at a predetermined frequency, as shown in FIG. 14. TheID module 100 causes the primary coil L11 and a capacitor C11 to produceparallel resonance. The coil module 110 is configured to have a closedloop by electrically connecting the ends of two coils L12 and L13 toeach other. Energy is transferred between the two coils L12 and L13 by acurrent. That is, a magnetic field is emitted when the current, which isgenerated by the coil L12 coupled with the primary coil L11, passesthrough the coil L13.

However, increasing the inductance value of the coil for emission L13and decreasing the inductance value of the coupling coil L12 in order toincrease the magnetic field energy to be received from the reader/writercauses the voltage at the ends of the coil L12 to decrease. Therefore,there is a problem in that the amount of current flowing between the twocoils L12 and L13 is decreased and sufficient energy is not transferredfrom the IC to the coil for emission L13, which reduces thecommunication distance. In addition, when the emission coil L13 is closeto the antenna of the reader/writer or is close to another wireless IC,the inductance value varies due to the mutual inductance and theresonant frequency of the primary coil L11 also varies. As a result,reading by the reader/writer may be disabled.

SUMMARY OF THE INVENTION

To overcome the problems described above, preferred embodiments of thepresent invention provide an antenna for a wireless IC device havingimproved energy transfer efficiency with a wireless IC, and a wirelessIC device including the antenna.

An antenna according to a preferred embodiment of the present inventionpreferably includes an antenna pattern, and spiral coupling patternscoupled to the antenna pattern and arranged so as to face each other.

A wireless IC device according to another preferred embodiment of thepresent invention preferably includes an antenna pattern, spiralcoupling patterns coupled to the antenna pattern and arranged so as toface each other, and a coupling module including a wireless IC and afeeder circuit substrate including a feeder circuit arranged to becoupled to the wireless IC, wherein the feeder circuit includes aninductor, and the coupling module is mounted on the coupling patterns.

In the antenna and the wireless IC device, the spiral coupling patternscoupled to the antenna pattern preferably are arranged so as to faceeach other to define a single LC resonator. That is, a capacitor isprovided between the spiral coupling patterns arranged so as to faceeach other, and LC resonance is obtained by using the capacitor andinductances produced by the spiral coupling patterns. This LC resonanceincreases the impedance to infinity, whereby energy is concentrated inthe coupling patterns. As a result, energy transfer efficiency betweenthe antenna and the wireless IC mounted thereon is improved.

In the antenna and the wireless IC device, the antenna pattern maypreferably be a single coil pattern, two coil patterns arranged so as toface each other, or two circular patterns including at least a pair ofends and arranged so as to face each other, and may preferably include adipole-type emitter coupled to the circular patterns, for example. Inparticular, more magnetic fields can be generated when two layers ofantenna patterns are arranged so as to face each other. In addition,when the antenna patterns, which are arranged in a pair, are coupled toeach other and the coupling patterns, which are arranged in a pair, arecoupled to each other, stray capacitance is prevented from occurringbetween the patterns even when multiple wireless IC devices are closethereto or a dielectric, such as a human hand, is close thereto, therebypreventing resonant frequency variations.

According to various preferred embodiments of the present invention, thetransfer efficiency between the antenna and the wireless IC is greatlyimproved and energy can be efficiently transferred.

The above and other elements, features, steps, characteristics, andadvantages of the present invention will become more apparent from thefollowing detailed description of the preferred embodiments withreference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view illustrating a wireless IC device accordingto a first preferred embodiment of the present invention.

FIG. 2 is a perspective view illustrating main components of thewireless IC device according to the first preferred embodiment of thepresent invention.

FIG. 3 is a perspective view illustrating enlarged coupling patterns ofthe wireless IC device according to the first preferred embodiment ofthe present invention.

FIG. 4 is a plan view illustrating a disassembled layered structure of afeeder circuit substrate to be mounted on the wireless IC deviceaccording to the first preferred embodiment of the present invention.

FIG. 5 is a perspective view illustrating main components of a wirelessIC device according to a second preferred embodiment of the presentinvention.

FIG. 6 is a plan view illustrating enlarged coupling patterns of thewireless IC device according to the second preferred embodiment of thepresent invention.

FIG. 7 is an equivalent circuit diagram of an antenna according to thefirst preferred embodiment of the present invention.

FIG. 8 is an equivalent circuit diagram of an antenna according to thesecond preferred embodiment of the present invention.

FIG. 9 is a plan view of a wireless IC device according to a thirdpreferred embodiment of the present invention.

FIG. 10 is a plan view of an antenna pattern arranged on the frontsurface side of the wireless IC device according to the third preferredembodiment of the present invention.

FIG. 11 is a plan view of an antenna pattern arranged on the backsurface side of the wireless IC device according to the third preferredembodiment of the present invention.

FIG. 12 is a plan view illustrating a disassembled layered structure ofa feeder circuit substrate mounted on the wireless IC device accordingto the third preferred embodiment of the present invention.

FIG. 13 is a graph illustrating the gain of the wireless IC deviceaccording to the third preferred embodiment of the present invention.

FIG. 14 is an equivalent circuit diagram illustrating a conventionalexample of a wireless IC device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An antenna and a wireless IC device according to preferred embodimentsof the present invention will be described below with reference to theaccompanying drawings. Note that common reference signs are used todenote the same members and sections in the drawings, and duplicateexplanation is omitted.

First Preferred Embodiment

A wireless IC device 1A according to a first preferred embodiment of thepresent invention preferably includes a substrate 10, a coupling module20, and an antenna 30, as shown in FIGS. 1 and 2. The coupling module 20includes a wireless IC chip 21 and a feeder circuit substrate 25including a feeder circuit arranged to be coupled to the wireless ICchip 21. The antenna 30 includes a coil pattern 31 and spiral couplingpatterns 32 a and 32 b that are provided at the ends of the coil pattern31 and arranged so as to face each other.

The substrate 10 is preferably made of a dielectric, such as a PET film,for example. The coil pattern 31 preferably has a coil shape on thefront surface of the substrate 10, as shown in FIG. 2. The spiralcoupling pattern 32 a is provided at one end thereof. The spiralcoupling pattern 32 b is arranged on the back surface of the substrate10 so as to face the coupling pattern 32 a. An end 32 c of the couplingpattern 32 b is electrically connected to the other end 31 c of the coilpattern 31 through a via hole conductor 33.

The wireless IC chip 21 includes a clock circuit, a logic circuit, amemory circuit, and other suitable circuits, as is known in the art, andnecessary information is stored therein. The wireless IC chip 21includes an input terminal electrode, an output terminal electrode, andmounting terminal electrodes, which are not shown. The feeder circuitsubstrate 25 is preferably, as described below with reference to FIG. 4,a layered substrate in which the feeder circuit including an inductor isembedded, and mounted (bonded) on the coupling pattern 32 a. Note that,although the coupling module 20 includes the wireless IC chip 21 and thefeeder circuit substrate 25 that are separately provided, a wireless ICand a feeder circuit may be integrally provided on a single substrate.

An example of the feeder circuit embedded in the feeder circuitsubstrate 25 will be described with reference to FIG. 4. The feedercircuit substrate 25 preferably includes a plurality of layered sheets41 a to 41 g including electrodes provided thereon. Each of the sheets41 a to 41 g is preferably made of ceramic or resin, for example.

Electrodes 42 a to 42 d are provided on and via hole conductors 43 a and43 b extend through the sheet 41 a. An electrode 44 is provided on andvia hole conductors 43 c and 43 d extend through the sheets 41 b to 41f. An electrode 44 is provided on the sheet 41 g.

When the sheets 41 a to 41 g are layered, the electrodes 44 of thesheets are electrically connected together through the via holeconductor 43 d, thereby forming an inductor. One end of the inductor (anend 44 a of the electrode 44 on the sheet 41 b) is connected to theelectrode 42 b on the sheet 41 a through the via hole conductor 43 b.The other end of the inductor (an end 44 b of the electrode 44 on thesheet 41 g) is connected to the electrode 42 a on the sheet 41 a throughthe via hole conductors 43 c and 43 a. The inductor resonates at apredetermined resonant frequency with the inductance thereof and thecapacitance between lines of the electrode 44.

The electrodes 42 a and 42 b on the sheet 41 a are connected to theinput terminal electrode and the output terminal electrode,respectively, of the wireless IC chip 21. The electrodes 42 c and 42 don the sheet 41 a are connected to the mounting terminal electrodes ofthe wireless IC chip 21. In addition, the inductor is magneticallycoupled to the coupling patterns 32 a and 32 b.

In the wireless IC device 1A, a high-frequency signal, for example, aUHF frequency band or an HF frequency band, emitted from thereader/writer is received by the coil pattern 31, and the feeder circuitmagnetically coupled to the coupling patterns 32 a and 32 b is resonatedto feed only a reception signal of a predetermined frequency to thewireless IC chip 21. The wireless IC chip 21 extracts a predeterminedenergy from the reception signal and reads the stored information usingthe energy as a driving source. After being matched to a predeterminedfrequency in the feeder circuit, the energy is emitted from the coilpattern 31 as a transmission signal through the coupling patterns 32 aand 32 b and transmitted to the reader/writer.

The coil pattern 31 is preferably an open type coil pattern. Thecoupling patterns 32 a and 32 b disposed at the ends of the coil pattern31 are arranged close to each other and define an LC resonator (see FIG.7). That is, a capacitor C is provided between the spiral couplingpatterns 32 a and 32 b arranged so as to face each other, and LCresonance is obtained using the capacitor C and the inductances L1 andL2 provided by the spiral coupling patterns 32 a and 32 b. This LCresonance increases the impedance to infinity, whereby energy isconcentrated in the coupling patterns 32 a and 32 b. As a result, theenergy transfer efficiency between the antenna 30 and the wireless ICchip 21 mounted thereon is significantly improved. In addition, sincethe two facing coupling patterns 32 a and 32 b are wound from the centerin opposite directions in plan view, the directions of current flow arethe same. Therefore, the directions of magnetic field are matched, andthe degree of coupling is improved.

Further, the resonant frequency of the feeder circuit substantiallycorresponds to the resonant frequency of the reception/transmissionsignal. That is, the resonant frequency of the resonance circuitdetermines the resonant frequency of the wireless IC device 1A.Therefore, communication can be performed at the resonant frequency ofthe resonance circuit independent of the resonant frequency of the coilpattern 31, and, thus, a combination of one type of antenna 30 and thefeeder circuit substrate 25 having various resonant frequencies isenabled. In addition, since the effects from other objects will notchange the resonant frequency of the resonance circuit, a stablecommunication with the reader/writer is obtained.

The resonant frequency of the coil pattern 31 is preferably set to behigher than the resonant frequency of the resonance circuit included inthe feeder circuit substrate 25. For example, when the resonantfrequency of the feeder circuit is about 13.56 MHz, the resonantfrequency of the coil pattern is preferably set to about 14 MHz. Thiscauses the feeder circuit and the coil pattern 31 to be magneticallycoupled at all times. For the antenna 30, the communication distance islarge when the resonant frequency thereof is close to the resonantfrequency of the resonance circuit. However, when a communicationfailure caused by another wireless IC device or a dielectric, such as ahuman hand, comes close to the antenna 30 is considered, it ispreferable that the resonant frequency of the coil pattern 31 is set tobe on the higher frequency side.

Furthermore, since the coupling patterns 32 a and 32 b are preferablydisposed directly under the magnetic field emitted from the feedercircuit substrate 25, and the inductor in the feeder circuit substrate25 preferably has a spiral shape so that the current flows in the samedirection as the coupling patterns 32 a and 32 b (the direction of thecurrent flowing in the inductor is shown as direction A in FIG. 4, andthe direction of the currents flowing in the coupling patterns 32 a and32 b is shown as direction B in FIG. 3), energy can be transferred moreefficiently.

Although the wireless IC chip 21 and the feeder circuit substrate 25 arepreferably electrically connected to each other, it is sufficient thatthe feeder circuit substrate and the antenna 30 are bonded to oneanother using an insulating adhesive agent, for example. Since bondingcan be achieved in any direction and the area of the coupling patterns32 a and 32 b is greater than the area of the feeder circuit substrate25, positioning is extremely easy when the coupling module 20 is mountedon the coupling pattern 32 a.

The feeder circuit substrate 25 is preferably made of a materialincluding a magnetic substance, for example. The Q value is relativelyhigh even when the embedded inductor is small, and thus, the size of thefeeder circuit substrate 25 can be reduced. When the feeder circuitsubstrate 25 includes a plurality of layers, the magnetic permeabilityof the layer at the side of the surface that is mounted on the couplingpattern 32 a is preferably relatively small (for example, using anon-magnetic layer). With a small magnetic permeability, a magneticfield is easily generated at an adjacent exterior portion, whereby acoupling force is increased only with the coupling patterns 32 a and 32b, and thus, interference caused by other objects is prevented.

Second Preferred Embodiment

A wireless IC device 1B according to a second preferred embodiment ofthe present invention preferably includes a substrate that issubstantially the same as the substrate 10 of the first preferredembodiment, which is not shown, the coupling module 20 and an antenna 50shown in FIG. 5. The antenna 50 preferably includes two coil patterns 51a and 51 b arranged on the front surface and the back surface,respectively, of the substrate so as to face each other, and spiralcoupling patterns 52 a and 52 b provided at one end of the respectivecoil patterns 51 a and 51 b and arranged so as to face each other. Thecoupling module 20 is preferably substantially the same as in the firstpreferred embodiment and is mounted (bonded) on the coupling pattern 52a. The communication configuration between the wireless IC device 1B andthe reader/writer is preferably substantially the same as that in thefirst preferred embodiment.

Also in the wireless IC device 1B, the coil patterns 51 a and 51 b arepreferably open type coil patterns. A capacitor C is provided betweenthe coil patterns 51 a and 51 b and between the spiral coupling patterns52 a and 52 b, which are arranged so as to face each other, and LCresonance is obtained by the capacitor C and the inductances L1 and L2defined by the two coil patterns 51 a and 51 b and the spiral couplingpatterns 52 a and 52 b (see FIG. 8). The LC resonance increases theimpedance to infinity, whereby energy is concentrated in the coilpatterns 51 a and 51 b and the coupling patterns 52 a and 52 b. As aresult, energy transfer efficiency between the antenna 50 and thewireless IC chip 21 mounted thereon is significantly improved. Inaddition, since two layers of the coil patterns 51 a and 51 b areprovided, more magnetic fields are generated. Furthermore, since thecoil patterns 51 a and 51 b, which are arranged in a pair, are coupledto each other and the coupling patterns 52 a and 52 b, which arearranged in a pair, are coupled to each other, stray capacitance isprevented from occurring between the patterns even when multiplewireless IC devices are close thereto or a dielectric, such as a humanhand, is close thereto, thereby preventing resonant frequency variation.Other effects and advantages achieved by the second preferred embodimentare the same as those of the first preferred embodiment.

In the second preferred embodiment, the entire antenna 50 resonates at apredetermined frequency. Therefore, when the coupling module 20 ismounted on the coupling patterns 52 a and 52 b, which are defined byportions of the antenna 50, the antenna 50 and the coupling module 20are coupled only by magnetic field at a predetermined frequency. Theantenna 50 and the reader/writer are coupled by electromagnetic field.

Third Preferred Embodiment

A wireless IC device 1C according to a third preferred embodiment of thepresent invention preferably includes a substrate 110, a coupling module120, and an antenna 130, as shown in FIG. 9. The coupling module 120preferably includes a wireless IC chip 21 and a feeder circuit substrate125 including a feeder circuit arranged to be coupled to the wireless ICchip 21.

The antenna 130 (the front surface side is shown in FIG. 10 and the backsurface side is shown in FIG. 11) preferably includes two circularpatterns 131 a and 131 b each having a pair of ends and arranged on thefront surface and the back surface, respectively, of the substrate 110so as to face each other, spiral coupling patterns 132 a and 132 bprovided at one end of the respective circular patterns 131 a and 131 band arranged so as to face each other, and two emitters 133 extending tothe sides from a portion of the circular pattern 131 a. The emitters 133are coupled to the circular pattern 131 a so as to function as ameandering dipole-type antenna.

An example of the feeder circuit embedded in the feeder circuitsubstrate 125 will be described with reference to FIG. 12. The feedercircuit substrate 125 preferably includes a plurality of sheets 141 a to141 d including electrodes provided thereon. Each of the sheets 141 a to141 d is preferably made of ceramic or resin, for example.

Electrodes 142 a to 142 d are provided on and via hole conductors 143 aand 143 b extend through the sheet 141 a. An electrode 144 is providedon and via hole conductors 143 c and 143 d extend through the sheets 141b and 141 c. An electrode 144 is provided on the sheet 141 d.

When the sheets 141 a to 141 d are layered, the electrodes 144 of thesheets are electrically connected together through the via holeconductor 143 c, thereby forming an inductor. One end of the inductor(an end 144 a of the electrode 144 on the sheet 141 b) is connected tothe electrode 142 b on the sheet 141 a through the via hole conductor143 b. The other end of the inductor (an end 144 b of the electrode 144on the sheet 141 d) is connected to the electrode 142 a on the sheet 141a through the via hole conductors 143 d and 143 a. The inductorresonates at a predetermined resonant frequency with the inductancethereof and the capacitance between lines of the electrode 144.

The electrodes 142 a and 142 b on the sheet 141 a are connected to theinput terminal electrode and the output terminal electrode,respectively, of the wireless IC chip 21. The electrodes 142 c and 142 don the sheet 141 a are connected to the terminal electrodes for mountingof the wireless IC chip 21. In addition, the inductor is magneticallycoupled to the coupling patterns 132 a and 132 b.

Also in the wireless IC device 1C, which is the present third preferredembodiment, the circular patterns 131 a and 131 b in the wireless ICdevice 1C are preferably open type circular patterns. Preferably, acapacitor C is provided between the circular patterns 131 a and 131 band between the spiral coupling patterns 132 a and 132 b, which arearranged so as to face each other, and LC resonance is obtained by thecapacitor C and the inductances L1 and L2 defined by the two circularpatterns 131 a and 131 b and the spiral coupling patterns 132 a and 132b. That is, the same equivalent circuit as in FIG. 8 is provided. ThisLC resonance increases the impedance to infinity, whereby energy isconcentrated in the circular patterns 131 a and 131 b and the couplingpatterns 132 a and 132 b. As a result, energy transfer efficiencybetween the antenna 130 and the wireless IC chip 21 mounted thereon issignificantly improved. Consequently, a high frequency signal isefficiently emitted from the emitters 133, and a high frequency signalreceived by the emitters 133 is efficiently transferred to the feedercircuit. In the wireless IC device 1C according to the third preferredembodiment, the circular patterns 131 a and 131 b are arranged so as tocouple to the feeder circuit and the emitters 133, whereby the loss of asignal transferred to the emitters 133 is reduced and a high gain isobtained. The gain of the wireless IC device 1C against frequency of ahigh frequency signal is illustrated as in FIG. 13. A high gain isachieved in a UHF frequency band.

Regarding the gain, a wider bandwidth can be obtained by changing theposition of coupling points K (see FIG. 9) of the circular pattern 131 aand the emitters 133. For example, a wider bandwidth can be obtained bymoving the position of the coupling points K close to the couplingpattern 132 a to increase the inductance value between the couplingpoints K. This is because when the inductance value between the couplingpoints K is increased, the bandwidth between two resonance pointsprovided by the emitters 133 is increased. Note that the circularpattern 131 a may preferably be replaced by a meander pattern or aspiral pattern, for example, in order to increase the inductance valuebetween the coupling points K.

In addition, since two layers of the circular patterns 131 a and 131 bare provided, more magnetic fields can be generated. Furthermore, sincethe circular patterns 131 a and 131 b, which are preferably arranged ina pair, are coupled to each other and the coupling patterns 132 a and132 b, which are preferably arranged in a pair, are coupled to eachother, stray capacitance is prevented from occurring between thepatterns even when multiple wireless IC devices come close thereto or adielectric, such as a human hand, comes close thereto, therebypreventing resonant frequency variations. Other effects and advantagesachieved by the third preferred embodiment are the same as those of thefirst preferred embodiment.

In addition, in the third preferred embodiment, the entire antenna 130resonates preferably at a predetermined frequency. Therefore, when thecoupling module 120 is mounted on the coupling patterns 132 a and 132 b,which are defined by portions of the antenna 130, the antenna 130 andthe coupling module 120 are coupled only by magnetic field at apredetermined frequency. The antenna 130 and the reader/writer arecoupled by electromagnetic field.

The antenna and the wireless IC device according to the presentinvention are not limited to the foregoing preferred embodiments.

As described above, preferred embodiments of the present invention areuseful in antennas and wireless IC devices used in RFID systems. Inparticular, preferred embodiments of the present invention are superiorin terms of the energy transfer efficiency with a wireless IC.

While preferred embodiments of the present invention have been describedabove, it is to be understood that variations and modifications will beapparent to those skilled in the art without departing from the scopeand spirit of the present invention. The scope of the present invention,therefore, is to be determined solely by the following claims.

1. An antenna comprising: an antenna pattern; and coupling patternscoupled to the antenna pattern and arranged so as to face each other. 2.The antenna according to claim 1, wherein the antenna pattern is a coilpattern; and the coupling patterns are provided at ends of the coilpattern.
 3. The antenna according to claim 1, wherein the antennapattern includes two coil patterns arranged so as to face each other;and the coupling patterns are provided at one end of each of the twocoil patterns.
 4. The antenna according to claim 1, wherein the antennapattern includes two circular patterns including at least a pair of endsand arranged so as to face each other, the antenna pattern including adipole-type emitter coupled to the two circular patterns; and thecoupling patterns are provided at one end of each of the two circularpatterns.
 5. A wireless IC device comprising: an antenna pattern;coupling patterns coupled to the antenna pattern and arranged so as toface each other; and a coupling module including a wireless IC and afeeder circuit substrate including a feeder circuit arranged to becoupled to the wireless IC; wherein the feeder circuit includes aninductor; and the coupling module is mounted on the coupling patterns.6. The wireless IC device according to claim 5, wherein the antennapattern is a coil pattern; and the coupling patterns are provided atends of the coil pattern.
 7. The wireless IC device according to claim5, wherein the antenna pattern includes two coil patterns arranged so asto face each other; and the coupling patterns are provided at one end ofeach of the two coil patterns.
 8. The wireless IC device according toclaim 5, wherein the antenna pattern includes two circular patternsincluding at least a pair of ends and arranged so as to face each other,and the antenna pattern including a dipole-type emitter coupled to thecircular patterns; and the coupling patterns are provided at one end ofeach of the two circular patterns.
 9. The wireless IC device accordingto claim 5, wherein the coupling module and the coupling patterns aremagnetically coupled.
 10. The wireless IC device according to claim 5,wherein the inductor has a spiral shape such that current flows in thesame direction as the coupling patterns.
 11. The wireless IC deviceaccording to claim 9, wherein a resonant frequency of the feeder circuitsubstantially corresponds to a resonant frequency of areception/transmission signal.
 12. The wireless IC device according toclaim 5, wherein a resonant frequency of the antenna pattern is higherthan a resonant frequency of the feeder circuit.
 13. The wireless ICdevice according to claim 5, wherein an area of the coupling patterns isgreater than an area of the feeder circuit substrate.
 14. The wirelessIC device according to claim 5, wherein the feeder circuit substrate ismade of a material including a magnetic substance.
 15. The wireless ICdevice according to claim 14, wherein the feeder circuit substrateincludes a plurality of layers and a magnetic permeability of a layer ofthe plurality of layers at a side of a surface that is mounted on thecoupling pattern is smaller than at least one other layer of theplurality of layers.